#include<string.h>
#include<stdio.h>
#include<stdlib.h>
extern char**environ;
int main(){
const char *who = getenv("USER");
if(who == NULL) return 1;

if(strcmp(who, "sw")==0)
{
    printf("这是程序的正常执行逻辑\n");
}
 else
 {
     printf("Only sw!!\n");
 }
}

